Congenital Malformations of Pulmonary and Intestinal
Lymphatic Flow
Complications of congenital malformations of lymphatic flow include
chylous effusions (thoracic cavity), chylous ascites (peritoneal cavity)
and, even more rarely, chylopericardium (pericardial cavity). These
complications are often seen in children with complex vascular anomalies
including generalized lymphatic anomalies (GLA), central conducting
lymphatic anomalies (CCLA), Gorham Stout disease (GS), and Kaposiform
lymphangiomatosis (KLA, a proliferative disorder) (Table 1) or
in children with known congenital syndromes associated with malformed
lymphatics including Down, Turner and Noonan syndromes. These
complications of lymphatic flow can result in systemic fluid and
electrolyte imbalance, nutritional deficiencies, hypovolemia, and
hypoalbuminemia. Progressive loss of essential proteins results in an
increased risk of hemorrhagic coagulopathy from lack of prothrombin and
fibrinogen.[3] Thrombophilia can occur due to loss of antithrombin.
There is an additional increased risk of infection from the loss of both
cellular (lymphocytopenia and low CD4+ T-cells) and humoral
(hypogammaglobulinemia) immunity resulting in progressive
immunosuppression.[4]
Congenital lymphatic leak can occur in utero due to obstructions and
leaks of the lymphatic system. The accumulation of large fluid volumes
in the thorax or abdomen can lead to cardiac failure and obstruction of
venous return leading to non-immune hydrops fetalis, polyhydramnios, and
fetal demise. Historically, mortality for congenital chylothorax has
been reported to be high around 10-20%.[5, 6] New imaging, surgical
and interventional techniques have reduced mortality significantly in
certain populations.[7]